ReadWriteWeb have a post on NoSQL (again?) by Audrey Watters which is a brief overview of the area. The original post points the Heroku blog, where Adam Wiggins outlines the uses of NoSQL. I’m not an expert by any means but use Redis on a daily basis with the Rediska PHP library. I remember having an argument with the IT director when I originally proposed using Redis but I’m glad that the gamble has paid off. The caching system that uses is now far more productive than the earlier version.
Our base is database is MySQL which I like a fair amount for what we do with it but all I needed do was to cache some data. The scripts write a fair amount of data to the cache and then there is one read process to read the entire list before updating the main database. At least I know that the data has some sort of security. It is not a panacea or similar cure all but it does have a place in development for certain jobs.
Best tool and all that?
I can understand why Twitter are not using Cassandra in the main service but are still using it for other projects. For now. Systems and priorities change and perhaps it will happen in some way.
Despite its meteoric rise, NoSQL is not the answer to everything. It does have a useful place though.